Our objectives are to study how facial expression and body movement provide leakage within an experimentally arranged deceptive interaction with normal subjects; to study these nonverbal behaviors in interviews with psychiatric patients, isolating those actions which change between admission and discharge from a mental hospital and those which distinguish among patients with differing psychiatric problems; to explore differences in the repertoire of nonverbal behavior among normal subjects and how they are related to personality, interpersonal style and temperament. Videotape records of deceptive interactions and of psychiatric interviews are the raw materials. The methods of research involve both direct measurement of the frequency of occurrence and duration of specific types of behavior (facial, hand, leg, posture, eye-contact) and presenting segments of the interviews to observers and studying how impressions vary with what is viewed (face vs. body).